Acceleration the bacterial biodegradation of crude oil pollution using Fe2O3 and ZnO nanoparticles

Abstract

Oil spill effects on environments and habitats can be catastrophic, where they can kill plants and animals, disturb salinity/pH levels, and pollute air/water. The aim of this work was to accelerate the biodegradation of crude oil by combination with nanoparticles (NPs). Two hundred and sixty-five bacterial isolates were selected from polluted soil and water samples. The most promising isolates were identified by 16S rRNA genes sequencing. Iron oxide nanoparticles (Fe<inf>2</inf>O<inf>3</inf> NPs) and zinc oxide nanoparticles (ZnO NPs) were synthesized and characterized. The SEM and TEM images of Fe<inf>2</inf>O<inf>3</inf> and ZnO NPs revealed that nanoparticles were mostly spherical in shape forming chain-like aggregates with average sizes 48 and 25 nm, respectively. The combination of Fe<inf>2</inf>O<inf>3</inf> NPs and biodegradation bacterial species Bacillus thuringiensis S1, Pseudomonas aeruginosa S2, and Psychrobacter faecalis S3 achieved 97.62, 97.23, and 97.89%, while with ZnO NPs were 96.27, 95.81, and 96.35%, respectively after 3 days only. This study proven that the biodegradation process improved and reaches 98 and 96% by a combination of selected optimum bacterial isolates with Fe<inf>2</inf>O<inf>3</inf> and ZnO NPs, respectively. The novel combination method between bacterial species and nanoparticles accelerated the biodegradation reaching up to 98% of crude oil within three days and can be used to enhance in situ bioremediation of petroleum contamination.